The invention relates to a method of manufacturing an electron gun component which comprises a number of electrodes having at least one aperture, at least two electrodes having positioning means and a jig having further positioning means to cooperate with the positioning means, in which method the electrodes are stacked in the jig and positioned by means of the positioning means and the further positioning means, and the at least two electrodes are interconnected.
Electron guns are used, inter alia, in display tubes for colour display devices, projection display devices and data display devices.
A method of the type described in the opening paragraph is known from the abstract in the English language of Japanese Patent Application JP-A 56-54739, published in Patents abstracts of Japan vol. 5. No. 117, (E-67), (789), Jul. 28, 1981. In the Application a description is given of a method of manufacturing an in-line electron gun. The electrodes have one central aperture and two outer apertures. The jig comprises a pin on which the electrodes are stacked, which pin penetrates the central aperture, and two fixed and two movable jaws. The jaws cooperate with the positioning means and the pin to position the electrodes. Each electrode comprises a projection on either side of the in-line plane which extends away from the plane.
After the electrodes of an electron gun have been positioned in a jig, the electrodes are interconnected which is normally carried out by pressing a rod of ceramic glass which is heated to the flow temperature onto the projections, said rod permanently interconnecting the electrodes after it has cooled.
It has been found that the edges of the central aperture may be damaged which leads to failure of the electron gun, and that an electrode sometimes sticks to the pin so that it is difficult to remove the electron gun component from the pin.